THE JAVASCRIPT 100 · LEARN BY EXPERIMENTINGSmall experiments.
Small experiments.
Real understanding.
Code your next idea.
A complete practice journey from your first value to reusable application logic. Read it, predict it, change it—and see what your code really does.
100 guided lessons210 behavior checks20 learning chapters
your next small discovery.js
TRY → OBSERVE → UNDERSTAND
const skills = ["read", "experiment", "build"];
skills.map(skill => `I can ${skill}.`);
01
Predict02
Run03
Explain
Predict02
Run03
Explain
✓
A failing check is your next clue.Learn with feedback you can inspect.
Real JavaScript execution · no signup · no API needed
YOUR PROGRESS
Your first discovery starts here.
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